<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>过渡</title>
    <style>
        img{
            width: 200px;
            height: 150px;
            transition: all 1s;
        }

        img:hover{
            width: 500px;
            height: 400px;
        }
    </style>
</head>
<body>
    <img src="../img/img01.jpg" alt="">
</body>
</html>